Synthesis of C-4-disubstituted analogues of N-acetylneuraminic acid

Abstract

The synthesis of some novel C-4-disubstituted analogues of N-acetylneuraminic acid has been achieved by nucleophilic opening of the epoxide ring in the acetyl-4,4′-anhydroneuraminic acid derivatives 6 and 7. This has provided the azide 8, the methyl ether 9, the nitrile 10 and the chloride 11 of the 8,9-isopropylidenated β-methyl ketoside of methyl N-acetylneuraminate in moderate to good yields.